a piece can be a good thing or a bad thing, depending on what/who you're talking about
-something thats awesome or looks good
-someone who has a fairly original personality -someone who is a crackup
-someone who is dumb
many think a piece is short for piece of shit--which its not so anybody who thought that is a fucking dumbass and needs to be shot
-Dude, look at that mustang! That car's a piece!
-Yeah, I know that kid. He's cool. Kid's a piece.
-LMAO THAT MUH FUCKERS A PIECE!
-Ugh, i hate him. That kids just a piece.
A person who you hold in unconditional positive regard with whom you share a relationship that purports all the benefits of marriage while simulaneously allowing all the benefits of being single.